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          Helium has unique properties that make it valuable for use in a wide range of applications. For example, its properties make possible faster cooling rates, which has led to adoption of helium in vacuum quenching technology, enabling many heat treaters to remain competitive and grow their business. However, helium is a finite resource. Because of a delicate balance between helium availability and increasing demand, it is imperative that the helium-producing industry work with helium end users to conserve, recover and recycle this resource. Technology for recovering and recyling helium developed by Sparco Group offers heat treaters an opportunity to significantly reduce costs. Helium gas quench benefits Vacuum furnace gas quenching using helium can result in higher production rates, improved metallurgical properties, and can reduce overall process costs. Lower heat-transfer properties of argon and nitrogen can require expensive furnace modifications, higher quench pressure and increased blower speeds to achieve the same cooling rates achieved using helium. Helium’s heat transfer coefficient is 60% greater than that of nitrogen at the same pressure. Also, helium is less dense than nitrogen or argon, which makes it easier to move in the furnace.




Furnace fans need less power to circulate helium, therefore, increasing fan speed or pressure becomes a cost-effective practice in accelerating cooling. Additional benefits of helium gas quenching include:
• Like argon, helium is inert and will not react with components being treated. Nitrogen is considered inert in most cases, but can form nitrides in certain materials. • Parts clean up is minimal compared with oil quenching.
• Helium quenching can open new markets for heat-treating processes that may be limited by conventional gas quenching. For example, heavier loads or parts with thicker cross sections can be quenched at a faster rate.

Helium Membrane Recovery 

In many applications, mixtures of Helium and e.g. air, nitrogen or argon are mostly used. By recovering the very valuable helium from these gas mixtures, very high cost savings can be realized. Recovery can take place by means of membranes. The very selective  Membrane developed by Evonik, together with the clever membrane configuration of Evonik, combines high product gas purity with a high helium yield.